I don't think any similar magnet exists that doesn't embed the magnet in a dewar full of liquid helium. And it probably doesn't make any sense to do it differen

I don't think any similar magnet exists that doesn't embed the magnet in a dewar full of liquid helium. And it probably doesn't make any sense to do it differently, even if it were possible. You need some mass here for the helium anyway as you never ever must run dry and it constantly evaporates.